Modeling and analysis of switched mode DC-DC converters for vehicular power systems

With the initiative for more electric (MEV), hybrid electric (HEV) and electric vehicles (EV), numerous electric loads have been added to the vehicular power system. Such changing trends have increased the use of switch mode DC-DC converter that would require very low conversion/duty ratios. Duty ratios close to zero greatly deteriorate O/P voltage/current and hence affect control signals. The use of cascaded DC-DC converters increases this conversion ratio. Different modeling techniques based on averaged, sampled-data and detailed model are discussed. Based on these modeling approaches, cascaded system behavior and dynamics are observed and the importance of hierarchical modeling is emphasized.